RT Journal Article SR Electronic T1 The genetic intractability of Symbiodinium microadriaticum to standard algal transformation methods JF bioRxiv FD Cold Spring Harbor Laboratory SP 140616 DO 10.1101/140616 A1 Jit Ern Chen A1 Guoxin Cui A1 Manuel Aranda YR 2017 UL http://biorxiv.org/content/early/2017/06/08/140616.abstract AB Modern transformation and genome editing techniques have shown great success across a broad variety of organisms. However, no study of successfully applied genome editing has been reported in a dinoflagellate despite the first genetic transformation of Symbiodinium being published about 20 years ago. Using an array of different available transformation techniques, we attempted to transform Symbiodinium microadriaticum (CCMP2467), a dinoflagellate symbiont of reef-building corals, in order to perform CRISPR-Ca9 mediated genome editing. Plasmid vectors containing the chloramphenicol resistance gene under the control of the CaMV p35S promoter as well as several putative endogenous promoters were used to test a variety of transformation techniques including biolistics, electroporation, silica whiskers and glass bead agitation. We report that we have been unable to confer chloramphenicol resistance to our specific Symbiodinium strain. These results are intended to provide other researchers with an overview of previously attempted techniques and sequences in order to support efficient planning of future experiments in this important field.